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71.
Cervical cancer is the most common gynaecological malignancy, with a high incidence rate and mortality rate in middle-aged women. Human bone marrow mesenchymal stem cells (hBMSCs) have been implicated in the initiation and subsequent development of cancer, along with the involvement of extracellular vesicles (EVs) mediating intracellular communication by delivering microRNAs (miRNAs or miRs). This study is aimed at investigating the physiological mechanisms by which EVs-encapsulated miR-144-3p derived from hBMSCs might mediate the progression of cervical cancer. The expression profiles of centrosomal protein, 55 Kd (CEP55) and miR-144-3p in cervical cancer cell lines and tissues, were quantified by RT-qPCR and Western blot analysis. The binding affinity between miR-144-3p and CEP55 was identified using in silico analysis and luciferase activity determination. Cervical cancer cells were co-cultured with EVs derived from hBMSCs that were treated with either miR-144-3p mimic or miR-144-3p inhibitor. Cervical cancer cell proliferation, invasion, migration and apoptosis were detected in vitro. The effects of hBMSCs-miR-144-3p on tumour growth were also investigated in vivo. miR-144-3p was down-regulated, whereas CEP55 was up-regulated in cervical cancer cell lines and tissues. CEP55 was targeted by miR-144-3p, which suppressed cervical cancer cell proliferation, invasion and migration and promoted apoptosis via CEP55. Furthermore, similar results were obtained by hBMSCs-derived EVs carrying miR-144-3p. In vivo assays confirmed the tumour-suppressive effects of miR-144-3p in hBMSCs-derived EVs on cervical cancer. Collectively, hBMSCs-derived EVs-loaded miR-144-3p impedes the development and progression of cervical cancer through target inhibition of CEP55, therefore providing us with a potential therapeutic target for treating cervical cancer.  相似文献   
72.
An investigation has been made of the staining properties of eight dyes of the thionin group. The dyes studied are as follows: tetra-ethyl thionin, asymmetrical di-ethyl thionin, tetra-methyl thionin (methylene blue), tri-methyl thionin (azure B), asymmetrical di-methyl thionin (azure A), symmetrical di-methyl thionin, mono-methyl thionin (azure C), and unsubstituted thionin. The staining properties were tested on sections of paraffin embedded material following five different methods of fixation. No counterstain was employed. It was shown that there was a general correlation between the extent of ethylation or methylation of the dyes and their staining properties. As one passes from tetra-ethyl thionin down the series to thionin itself, there is a progressive decrease in the amount of green showing in the preparations, and an increase in the amount of red present, also an increase in the metachromatic effects, and in the intensity of nuclear staining. There seems, also, to be a similar relation between staining qualities on the one hand and the color and solubility of the dye base on the other.  相似文献   
73.
Abstract

If the entire discipline of diagnostic cytopathology could be distilled into a single theme, it would be the Papanicolaou stain. Yet it was the Romanowsky stain upon which the discipline of cytopathology was founded. Both stains are used today in the cytopathology laboratory, each for a different and complementary purpose. We trace the history of cytopathological stains and discuss the advantages and limitations of Romanowsky-type stains for cytological evaluation. We also provide suggestions for the advantageous use of Romanowsky-type stains in cytopathology.  相似文献   
74.
Human papilloma virus (HPV) infection is the main etiological factor for cervical intraepithelial lesions (CIN). An important characteristic of this process is the loss of genome stability. Therefore, it is imperative to use biomarkers of DNA damage caused by genomic instability to identify high risk individuals. We investigated the frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) of 20 patients, diagnosed as histologically CIN 1 and 10 healthy controls. We also examined the frequency of other nuclear anomalies including nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in PBL of patients with CIN 1 and healthy controls, and evaluated the benefits of p16INK4a and Ki-67 (p16INK4a/Ki-67) immunohistochemical double staining for identifying cervical squamous cells that express HPV E6/E7 oncogenes. We analyzed the association between the frequency of MN in PBL and the amount of p16INK4a/Ki-67 co-expression in CIN 1 patients to establish genomic instability. Among CIN 1 subjects, 15% exhibited diffuse p16INK4a/Ki-67 co-expression and were considered high positive, 25% of the CIN 1 cases exhibited p16INK4a/Ki-67 co-expression restricted to the lower part of the epithelium and were considered low positive and the remaining 60% of cases were negative. The frequency of MN, NPBs and NBUDs differed significantly among groups. We found a statistically significant positive correlation between p16INK4a/Ki-67 co-expression and the frequency of MN, NPBs and NBUDs in PBL. Our findings demonstrate the efficacy of p16INK4a/Ki-67 double immunostaining for histological samples with CIN 1. MN frequency in PBL might be useful for detecting genomic instability in cases of HPV infection and CIN.  相似文献   
75.
Abstract

A survey of all the 154 scientific publications of Emilio Battaglia (1917–2011) is presented, grouped in three main research interests – plant embryology, cytogenetics in plants and cytological terminology – plus other less relevant contributions. Battaglia's past and present role in these disciplines is briefly discussed, in the light of current research on these topics, partly reviewed also in other contributions of the present Plant Biosystems issue.  相似文献   
76.
The miR-302-367 cluster is specifically expressed in human embryonic stem cells and has been shown to convert human somatic cells into induced pluripotent stem cells. Here, we investigated the role of the miR-302-367 cluster in cervical carcinoma. The cluster was not endogenously expressed in cervical cancer cells, and its ectopic expression did not reprogram the cervical cancer cells to an embryonic stem cell-like state. However, ectopic expression of the miR-302-367 cluster in HeLa and SiHa cervical cancer cells inhibited cell proliferation and tumor formation by blocking the G1/S cell cycle transition. We identified a new cell cycle regulatory pathway in which the miR-302-367 cluster directly down-regulated both cyclin D1 and AKT1 and indirectly up-regulated p27Kip1 and p21Cip1, leading to the suppression of cervical cancer cell proliferation. Our findings suggest that the miR-302-367 cluster may be used as a therapeutic reagent for the treatment of cervical carcinoma.  相似文献   
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79.
Cervical cancer holds one of the highest morbidity and mortality in various types of cancers. It even leads to the most number of cancer-related deaths of women. A lot of research has indicated that the anomalous expression of long noncoding RNAs (lncRNAs) would induce carcinogenesis and is associated with poor prognosis of patients with cancer. However, the function and mechanism of many lncRNAs still call for further research. Tumor Protein P73 Antisense RNA 1 (TP73-AS1) is no exception. LncRNA TP73-AS1 has been found to promote cancer progressions in various cancers. It is upregulated in cervical cancer cells. The proliferation and migration ability of cervical cancer cells can also be boosted by TP73-AS1 in return. Meanwhile, miRNA-329-3p is downregulated in cervical cancer cells and could bind with both TP73-AS1 and ADP Ribosylation Factor 1 (ARF1). TP73-AS1 inhibited miR-329-3p expression while miR-329-3p inhibited ARF1 expression. More importantly, TP73-AS1 can positively regulate ARF1 expression. Based on all these experiments, TP73-AS1 regulates ARF1 expression by competitively binding with miR-329-3p, thus regulating cervical cancer progression. Further rescue assays confirmed TP73-AS1 regulates cervical cell proliferation and migration via miR-329-3p/ARF1. TP73-AS1 might serve as a novel regulator in cervical cancer.  相似文献   
80.
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